Sheilashu wrote:Consistent, even heat
Coal stokers are thermostatically controlled just like propane or wood pellets, it's on demand heat. Propane is going to have one small advantage here, if you wanted a little heat at this time of the year you can turn it on and off easily but since you have electric I guess that's really not an issue.
Optionally a hand fired stove is a little more work but a lot less than regular wood, even a hand fired stove can provide relatively uniform heat. I'm mentioning these because they do not need to power to operate so it's something else to consider, talk to your neighbors and find out how often and long power outages are. Realize living there if you have a big enough storm it might be 3+ days without power, that might only happen once every few years but expect it. Plan for a generator or heat that doesn't require power.
You mentioned an insert, they make coal inserts but they are hand fired. Typically you are going to have to service it twice a day. People usually get on 12 schedule with these. If you have open floor plan design it will work very well, if not you will have to figure out how to move the heat into other rooms, typically with cold air return. You put a duct at the furthest end on the house and then run it back to the area the stove is in. These work best when the unit is in the basement but you can incorporate fan in it.
Cost for install and monthly rates
The cost for the propane unit should be cheaper but I'd imagine because of the cost of running the propane lines it will be more overall. Comparing the coal and pellet stoves there is big cost difference between the $1K Home Depot pellet stove and a $3K Harman pellet stove. There is no Home depot brand coal stoves so make sure you are comparing the costs coal stoves to the better pellet stoves. If you are comparing apples to apples costs should be similar.
Fuel rates are going to favor coal, the only thing that will even come close is natural gas if you are in town with piped supply.
Dust/ash (I've had ashthma and our dogs sleep in the basement)
I can't speak from experience but from other what I gather the dust/dirt is about the same. There is things you can do to help prevent it with coal. They sell oiled coal for starters.
Relatively hassle free
Coal and pellets both involve some work, the coal is less work. For starters for every 3 tons of pellets you need to move you only need to move about 2 tons of coal.
Access (we live on a very steep hill)
If you are getting delivery this is issue no matter what fuel. You live in an area where bulk delivery is available, if you have a basement window near the driveway the best thing to do is build a bin big enough for what you expect to use for the season inside the basement. Get it all at once in the summer into the fall, this is the best time of the year to get it because it will be the cleanest. If you get it in the summer it's a little cheaper. Plus if you have the stoker in the basement you only have to walk over to the coal bin for the coal.
This is one big advantage coal has over pellets, it's a lot less storage space required and it can be stored anywhere indefinitely. You can dump it on the ground if you want however I'd suggest tarping it top and bottom if you were going to do that. It will burn wet but you want to avoid that it will freeze together and because of corrosion issues in the hopper.
As side note if this is your driveway coal ash makes excellent anti skid material.
Long term feasibility [able to still maintain in our golden years (retire in 10 years), resale value]
You have to figure you might be moving 40 to 60 pounds of coal per day on average for 5 months. There is ways to help eliminate the work, some people have set up vac systems for example to move the coal from the bin to the hopper. Gravity is your friend, a coal bin at ground level can be piped with pvc into a basement level hopper.
Propane Stove in basement plus insert on main level
You can get a small coal furnace to handle both and it's not much more than regular stove. You'd have to run some duct work.